The present invention relates in general to a communication system that provides an automated and simplified interface between a vehicle and an emergency response center using cellular telephone communications, and more specifically to selecting cellular phone operating modes that maximize the ability to successfully complete a call from the vehicle to the response center or from the response center to the vehicle.
The use of transportation vehicles such as automobiles on roads and highways inevitably involves some number of breakdowns or collisions, or situations involving health difficulties of a driver or a passenger in which roadside vehicle service, such as a tow truck, or emergency assistance, such as police, ambulance, or fire, are needed. A means of summoning help is desirable in such situations and the availability of radio communications has been very beneficial in that regard. Cellular telephones are often installed or carried in vehicles by their owners for this reason.
The response time to a request for help should be minimized to meet any potential need for critical services. Accurate information must be provided to the emergency service provider to permit effective and timely response. However, many cellular phone callers to emergency services are unable to provide their location accurately in a timely manner. In addition to position information, a service provider benefits from having information on vehicle identification, cellular phone number of the telephone in the vehicle, the cellular system identification from which a call originated, and speed and heading of a vehicle.
Automatic position locating systems such as a global positioning system (GPS) receiver have been utilized in conjunction with a cellular telephone unit to provide position information over a cellular link. Copending U.S. applications Ser. No. 08/419,349 and Ser. No. 08/419,350, each entitled "Vehicular Emergency Message System", describe a communication system which has high reliability and ease of use based on an automated interface between the vehicle and the response center.
An individual cellular telephone installed in a vehicle may be set-up by the owner in such a way that only some specific cellular communications are permitted while other possible communications are inhibited. These restricted operating modes can arise from a desire to avoid using certain cellular service providers (i.e., carriers) or geographic areas or from a desire to restrict the numbers which can be called from the individual phone as determined by the owner. However, these restricted operating modes or service levels of the cellular telephone can interfere with the ability of an emergency message system to contact a response center or with the ability of the response center to place a return call to the cellular telephone.